Question

What is the length of EF in the triangle? Show your work. HELP!

Answer 1

The length of EF in the given triangle is 8.80 m.

Step-by-step explanation:

Step 1:

In the given triangle, the opposite side's length is 16.2 m, the adjacent side's length is x m while the triangle's hypotenuse measures 16.2 m units.

The angle given is 90°, this makes the triangle a right-angled triangle.

So first we calculate the angle of E and use that to find x.

Step 2:

As we have the values of the length of the opposite side and the hypotenuse, we can calculate the sine of the angle to determine the value of the angle of E.

$sinE = \frac{oppositeside}{hypotenuse} =\frac{13.6}{16.2} = 0.8395.$

$E = sin^{-1} (0.8395), E = 57.087.$

So the angle E of the triangle DEF is 57.087°.

Step 3:

As we have the values of the angle and the hypotenuse, we can calculate the cos of the angle to determine x.

$cos E = \frac{adjacentside}{hypotenuse} = \frac{x}{16.2} .$

$cos(57.087) = 0.5433, x = 16.2 (0.5433) = 8.8014.$

Rounding this off to the nearest hundredth, we get x = 8.80 m.